1. Field of the Invention
The present invention generally relates to a tray for storing a semiconductor integrated circuit device and, more particularly, to a tray for storing a semiconductor integrated circuit device such as a ball grid array type or pin grid array type semiconductor device which has wiring terminals on the lower surface of its package.
2. Related Background Art
As the package types of semiconductor devices, ball grid array type and pin grid array type are well known. In the former type, as shown in FIGS. 1 and 2, ball terminals 1 serving as wiring terminals are arranged in a matrix on the lower surface of a package 2. The package 2 shown in FIGS. 1 and 2 is comprised of a substrate 3 and a molded resin 4 covering the upper portion of the substrate 3. In the latter type, lead pins (not shown) are used in place of ball terminals 1. Both of these types have features that the number of wiring terminals can be increased and that electric noise is small, compared to a general quad flat package.
Generally, a ball grid array type (xe2x80x9cBGAxe2x80x9d) semiconductor device 5, or a pin grid array type (xe2x80x9cPGAxe2x80x9d) semiconductor device is stored in the storage portion of an exclusive tray to be transported or subjected to tests. A storage portion in a conventional tray is a recess having almost the same shape as that of the package of the semiconductor device. The terminals of the semiconductor device should not be brought into contact with the tray. Therefore, through holes or recesses for receiving a ball terminal group or lead pin group are formed in the central portion of the bottom surface of the storage portion. Accordingly, the conventional tray supports the peripheral portion (a portion outside the outermost ball terminals or lead pins and indicated by reference numeral 2 in, e.g., FIG. 2) of the lower surface of the package of the semiconductor device with the peripheral portion of the bottom surface of its storage portion, and restrains horizontal movement of the package with the wall surface of the storage portion.
When the width of the peripheral portion of the lower surface of the package is small, the ball terminals or lead pins may come into contact with the inner wall surface of the terminal-accepting hole, or the edge of the package may enter the hole. Particularly, this problem becomes conspicuous in recent years because, as the package becomes more and more compact, the width of the peripheral portion of the lower surface of the package becomes narrow.
It is an object of the present invention to provide a tray for storing a semiconductor device, such as a BGA device or PGA device, having wiring terminals on the lower surface of its package, which can reliably support the semiconductor device regardless of the width of the peripheral portion of the lower surface of the package without causing the wiring terminals to come into contact with the wall surface of the storage portion.
In order to achieve the above object, according to the present invention, there is provided a tray for a semiconductor device such as a BGA device, comprising a substantially planar main body and a first storage portion provided on a first surface of the main body for storing the semiconductor device. The first storage portion has a first wall surface adapted to be arranged around the semiconductor device upon storing the semiconductor device. Also, the first wall surface has a first area which is inclined with an angle so as to support an edge of the package of the semiconductor device but not to come into contact with the wiring terminals.
With this arrangement, the inclined first area can come into contact with only the edge of the package to support the package.
In order to stabilize the semiconductor device stored in the storage portion, the first wall surface is preferably formed with a second area extending upward from an upper edge of the first area. It is effective if this second area is inclined with an angle larger than the angle of the first area.
The tray according to the present invention is also characterized by further comprising a second storage portion provided on a second surface of the tray main body opposite to the first storage portion, that can store a semiconductor device with wiring terminals thereof facing upward when the tray is turned over, wherein when a tray of the same type is stacked on this tray, the second storage portion of one tray cooperates with the first storage portion of the other tray to form a space for storing the semiconductor device.
With this arrangement, the vertical movement of the semiconductor device stored in the tray can be minimized or suppressed. When the trays are stacked and turned over, the semiconductor device can be easily transported to the second storage portion of the lower tray.
The second storage portion may comprise a second wall surface having a third area which is arranged around the semiconductor device upon storing the semiconductor device with the wiring terminals thereof facing upward, and which is inclined with an angle so as to support the edge of the package of the semiconductor device. When the tray has such a inclined area, the semiconductor device can be supported with only the edge of its package.
When the package of the semiconductor device has a rectangular or square lower surface, the first storage portion is preferably comprised of four first wall surfaces arranged to form a rectangular or square shape, and the first areas of the first wall surfaces preferably respectively support edges of the lower surface of the package of the semiconductor device.
The present invention will be more fully understood from the detailed description given hereinbelow and the attached drawings, which are given by way of illustration only and are not to be considered as limiting the present invention.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will be apparent to those skilled in the art from this detailed description.